1. Field of the Invention
The present invention relates to a communication apparatus that is capable of performing wireless communication with a plurality of host computers, and a method of controlling the communication apparatus.
2. Description of the Related Art
Conventionally, as disclosed in Japanese Laid-Open Patent Publication No. 2007-251851, there has been proposed a wireless USB formed by making USB wireless which is one of standards used in a personal computer (PC) environment as an interface for connection to peripheral devices.
In the wireless USB communication, it is impossible for a plurality of host computers to simultaneously communicate with one MFP (Multi-Function Peripheral), but it only possible to perform communication between one host computer and one MFP. This is stipulated in the standard of wireless USB (Wireless USB Specification Rev. 1.0).
Now, a description will be given of the following situation, by way of an example, in an environment in which a plurality of host computers (PCa, PCb, PCc) and a communication apparatus (MFP) are capable of performing wireless USB communication.
First, the PCa requests the MFP to connect thereto, and the PCa and the MFP become connected to each other. Then, in response to a facsimile transmission request received from the PCa, the MFP performs facsimile transmission of data received from the PCa to another facsimile machine via a public communication line network. Then, after the processing of the facsimile transmission is completed, the MFP sends a processing result (success or failure of the transmission) to the PCa which is the sender of the request.
In performing such processing, however, there can arise the following problem: There is a case where the transmission rate of facsimile transmission from the MFP is much slower than the speed of data transmission from the PCa to the MFP. In this case, to confirm the result of facsimile transmission by the PCa, even though the data transmission from the PCa to the MFP has been completed, it is required to maintain the connection between the PCa and the MFP without performing disconnection until the facsimile transmission is completed. Therefore, this causes the MFP to be uselessly occupied by the PCa, so that users of the PCb and the PCc have to wait for a long time.
FIG. 18 is a schematic diagram useful in explaining the above-mentioned situation. When the MFP accepts a connection request (701) from the PCa, the MFP connects to the PCa, and receives a FAX transmission JOB from the PCa (702). Then, the MFP stores data received from the PCa in an image memory thereof, and performs facsimile transmission of the data to a destination receiver via the public communication line network by controlling a modem thereof.
The transmission rate of this facsimile transmission is specified in ITU-T recommendation V. 34 and T. 30, and is 33. 6 kbps at the maximum. On the other hand, in the case of wireless USB communication, assuming that it is possible to obtain the same speed as that of USB 2.0, the transmission rate is 480 Mbps. As a consequence, after the transmission of the data in 702 is completed, the PCa and the MFP remain connected to each other until the processing of the facsimile transmission is completed.
Then, upon completion of the processing of the facsimile transmission, the MFP notifies the result of the transmission processing to the PCa (705), and then the PCa and the MFP are disconnected from each other (706). In other words, before the processing of the facsimile transmission is completed, it is impossible to accept the connection requests 703 and 704 from the PCb and the PCc which are the other host computers.
On the other hand, it can be envisaged to terminate the connection between the PCa and the MFP without waiting for completion of the facsimile transmission after the data transmission from the PCa to the MFP is completed. In this case, the PCa requests the MFP again to connect thereto (reconnection request), whereby the PCa and the MFP become connected to each other, and then the MFP notifies the result of the transmission processing to the PCa.
FIG. 19 is a schematic diagram useful in explaining a process for terminating the connection between the PCa and the MFP without waiting for completion of the facsimile transmission after the data transmission from the PCa to the MFP is completed. In response to a connection request (801) received from the PCa, the MFP connects to the PCa and receives a FAX transmission JOB from the PCa (802). Then, the MFP stores data received from the PCa in the image memory, and performs facsimile transmission of the data to the destination receiver via the public communication line network by controlling the modem.
In this case, differently from the FIG. 18 case, the MFP notifies predetermined information (e.g. receipt number) to the PCa (803), and terminates the connection to the PCa without waiting for completion of the processing of the facsimile transmission (804). Therefore, if the PCb, for example, requests the MFP to connect thereto (805) and requests the MFP to execute a printing process (806), the MFP can execute the printing process by controlling a recording section thereof. Further, if the PCc, for example, requests the MFP to connect thereto (809) and requests the MFP to execute a scanning process (810), the MFP can execute the scanning process by controlling a scanner thereof.
However, in this case, even if the PCa requests a reconnection so as to confirm the transmission result, if the MFP is in a state connected to the other host computer (PCb or PCc), the PCa cannot be connected to the MFP, and hence it takes a long time before confirming the transmission result. That is, even if the PCa requests a reconnection in 807, since the MFP has been connected to the PCb, the MFP cannot connect to the PCa. Similarly, even if the PCa requests a reconnection in 811, since the MFP has been connected to the PCc, the MFP cannot connect to the PCa. That is, this causes a problem that the PCa cannot confirm the transmission result until the MFP and the PCb are disconnected (808) and further the MFP and the PCc are disconnected (813).